A Ringbom Engine

[doc1955]

Well I grit blasted the other 3 base's and got a coat of primer put on.

Spent more time playing with the one that I have put together then working on getting the other 3 together.
It seems like that's usually the way it is for me it like a new toy just can't leave it alone. I need to get the heat shields made up and bent. Oh well later right now one more run :big:

 

[kcmillin]

Runs Great on a candle Doc, Awesome.

I know what you mean when you say its like a new toy. I have to move my finished engines, or should I say distractions, out of the shop, otherwise I keep playing with them, instead of building them.

Kel

 

[ksouers]

Hey Doc! Man, that sure runs great!

I didn't know you were that far along in the build. Sneaky...


Congrats on the runner. I'm sure the others will turn out just as well.

 

[doc1955]

Kel
I may have to do that or put them up on a high shelf I had to do that with my IC engines I was always running them now I have to get a step ladder to get them down so the now get to rest more.
I must have 100 hours run time on the fan I just built it is finally get a break with me playing with the Ringbom. :big:

Thanks Kevin I hope to get them done this week end one is suppose to be a Birthday gift for My father-in-law
He really likes the fan I built so I know he'll like this.

 

[doc1955]

Well I got the bases painted flywheels painted and the second engine put together and its a runner.
I did think she wasn't going to be at first. I ended up getting it all put together and she just refused to run.
So I pulled it apart and discovered I had forgotten to loctite power cylinder cap in place and she was leaking. Put some loctite on and put it back together and she ran. So now only 2 remaining to be assembled then I need to work on the burners and heat shields.

Here is a shot of the 2 together.

Here is a pic of the flywheel.




Here is a short video of the 2 of them running. The video isn't to good I don't have a steady enough hand.
[ame]http://www.youtube.com/watch?v=FjViV2Hnu7U[/ame]

 

[doc1955]

Well I did get 3 of the 4 to run. Number 4 is being a pain. I put it together and took it apart at least 5 or 6 times. She just doesn't want to run. I may have to polish the displacer rod it seems to have a high spot and keeps hanging up least ways that's what I guessing the cause.
Here is a vid of the 3 runners.
I wish I wouldn't of painted the bases now oh well. I am going to mount them on a bigger wood base so they don't dance all over the place they need a little more weight.

[ame]http://www.youtube.com/watch?v=XikgrFRXrB4[/ame]

 

[doc1955]

Well got number 4 figured out it was the high spot on the displacer rod it was about .0004 bigger in just one small area but enough to hang it up.
Here are a couple pics of them I'll try and get a better video if the miss's will let me borrow here video camera.

Still want to mount them on wooden bases to add more weight to them.

 

[kcmillin]

They all Look Real Great Doc!! Well Done!

I would like to see this engine on a high speed camera and watch exactly when everything happens.

I was wondering if the displacer cylinder could be placed horizontal?

Also, what are the bore's and strokes of the pistons? I am interested in designing and building one of these, and I like to go with what works, and yours works Awesome.

Kel

 

[doc1955]

Thanks Kel!

I don't know about laying the displacer horizontal you would I suspect incorporate some type of device to push the displacer back plus there would be extra drag on the displacer rod in the bushing due to the weight of the displacer hanging out on the end. Granted it doesn't weigh much but I think it would be enough to bring it to a stop.
The swept volume I used in this engine is 2cc

the displacer dia = .625
displacer stroke =.625
displacer rod dia =.219
displacer gap in hot tube=.015
power piston dia =.500
power stroke = .625

You need to try and keep the displacer and rod assembly as light as you can the lighter the better running and more RPM it will achive.

 

[kcmillin]

Thanks for the info Doc.

I was not sure if gravity was a helper or not. Now I know, Thanks.

Kel

 

[NickG]

Doc - wow! What a result ;D :bow:

Brilliant to run on a candle too, sorry I should have mentioned it would sut everything up!

Nick

 

[doc1955]

Thanks Nick
They will run on a pretty small flame. I have all four done now Saturday one will go to a new home for my father-in-laws 88th birthday. One I'm eventually going to put up for sale to try and help out our local humane society they need all the help they can get.

 

[NickG]

Nice idea selling one for charity doc :bow:, my poppin is going to by dad for his birthday, things like this make special presents.

 

[doc1955]

Oh I'll bet he'll like the poppin engine!

I've built a few engines for my father in law if I remember right the flame eater published in the Home shop machinist mag was the first I built for him and the he had to show it to half the town! Anyone that came by got to see it run. So after that I've been building little engines for him. It a lot easier for me now that I have machines at home and can work on them at my leisure.
Was going to present him with his new Ringbom this week end but it now looks like it will be next weekend.
Plan on take him and so others out for supper and present him with it. (good thing I built 4 I'd have his wore out before he gets it) :big:

I really should set them up and get some video of all 4 of them running before I break up the set.
My next build is going to be a Atkinson cycle hit-miss engine I don't know if I'm going to go through the effort of takin pictures and posting a build thread for them. It will be a double build as it will be a Christmas present. I have never built any Atkinson cycle engines and have only seen 1 in real life at a model show I attend every year.
Thanks for the comments on the build thread NickG I may make one more post if I get some good video of all 4 running.